from the Forum department...Driving a Stepper Motor
I am seeking advice on the best methods to effectively control a stepper motor.
from the Instrumentation department...ML1400 PLC communicate PIC 16f874 over modbus protocol
ML1400 PLC communicate with PIC 16f874 over modbus protocol and write data to LCD connected to microcontroller
from the Automation department...DCS Yokogawa Communication Issue
Yokogawa DCS communication with Modbus slave device using ethernet redundant connection with ALE111.
By Elbert van der Bijl on 17 April, 2014 - 5:15 am -
this behavior is by design and it will not occur when the Modbus slave is correctly responding to...
from the Automation and EMS department...Modbus Data transmission time
How to calculate time to receive data from slave to master in daisy chain connection of slaves, if my slaves are 20 and single master.
By Patrick Lansdorf on 16 April, 2014 - 1:55 am -
Hi, I have made a simple Excel sheet, where one can calculate the line time. You will need to...
By Steve Myres on 15 April, 2014 - 12:55 pm -
Slick idea on the prefetch! ...
By Lynn August Linse on 15 April, 2014 - 9:31 am -
>> What's a rule-of-thumb value for >> RTU-TCP latency in a Digi Modbus bridge...
By Bhadresh Sarvaiya on 15 April, 2014 - 1:29 am -
> Mr. Linse, > What's a rule-of-thumb value for RTU-TCP latency in a Digi Modbus bridge...
Mr. Linse, What's a rule-of-thumb value for RTU-TCP latency in a Digi Modbus bridge product? ...
By Lynn August Linse on 14 April, 2014 - 10:36 am -
Just be careful to accommodate the delay-back off during failure. With a single device, it might...
By Bhadresh Sarvaiya on 13 April, 2014 - 5:14 am -
Thank you for your kind reply.. but i didn't get answer as i want.. i didn't understand your...
You know - the word size, 11 bits - the number of words in the master message - silent...
from the Forum department...SCADA RTU in Substation
Why use SCADA RTU in a substation? What is the purpose of SCADA RTU?
from the Urgent department...Time and Date in Honeywell control builder
How could use time and date in control module?
thank you so much sir but unfortunately i couldn't find variables CEE1.HOUR...... i have many...
By Robert Perez on 9 April, 2014 - 9:05 am -
Hi Mostafa, you could get the hour, minute and second variables from the CEE under the...
from the Forum department...8-bit data types in Modbus registers
Are 8-bit data types obsolete for Modbus?
By Lynn August Linse on 14 April, 2014 - 10:39 am -
A bit of historical trivia... Modbus never had 8-bit data types. The original PLC were made back in...
> Since registers are always 16 bits, does it even make sense to provide data types of 8 bits...
from the Engineering department...Siemens marshaling wire
Brand name of Siemens' 0.5mm thick marshaling wire
from the Annoying Exceptions department...Negative Acknowledge and Bad Karma
How do you feel about security exceptions not being, you know, informative?
By JulieInAustin on 13 April, 2014 - 2:24 pm -
> What product are you working on, and are there any other security enhancements you are making?...
from the Automation List department...Interfacing VFD with PLC
How to interface variable frequency drives with PLCs?
By N.A. on 12 April, 2014 - 5:02 am -
If You Want only on/off control from PLC, then connect the drive to digital output module. and if...
from the Forum department...Connecting Honeywell UDC via Modbus TCP/IP to Modicon quantum
Connecting a Honeywell UDC temperature controller to Modicon PLC via Modbus. any ideas on this?
Latest edition of Honeywell's Modbus RTU communications manual 51-22-25-66, Rev T, dated February...
from the maintenance department...Process Switches NO NC definition
What "normally" means in process switches.
By N.A. on 11 April, 2014 - 1:51 am -
Dear Sir, Normally means then initial condition of any switch or relay without pressing or...
from the Instruments Department department...Modbus Max. Length
Measure the total Modbus Length
By Curt Wuollet on 10 April, 2014 - 9:31 pm -
No that's a star and it's a bad idea because 20 M of unterminated cable will give you reflections...
By Franco Kew on 10 April, 2014 - 5:43 am -
Dear CWW, Maybe I use the wrong wording in my post, but I am not using the star topology. I try...
By Steve Myres on 9 April, 2014 - 1:01 pm -
Hadn't thought of segmenting the network with repeaters to fix the topology - slick! Franco,...
By Lynn August Linse on 9 April, 2014 - 9:46 am -
This is an RS-485 issue, not Modbus question. Max length is more an issue of the cable quality...
By Steve Myres on 9 April, 2014 - 12:00 am -
You're not supposed to run RS485 in a star topology. Not sure if short branches are officially...
By Curt Wuollet on 8 April, 2014 - 11:19 pm -
That doesn't sound like a workable configuration. 485 doesn't like star layouts. You can use...
from the Automation List department...Android tablet for HMI?
Using an Android tablet as an all in one PLC.
By Ramses on 10 April, 2014 - 2:18 pm -
Hello, I found a very good free apps for android and IOs devices (Iphone, Ipad) that is a SCADA...
Gary, I've got a powered USB 4-port hub connected to my Nexus 7. I would think such a device...
You need to connect the power supply lines in the USB connection to a high-current source that can...
from the Instrumentation department...communication between siemens PLC S7-400 to DCS Centum CS3000R3
Communication between SIEMENS S7-400 PLC Scalance card to Yokogawa DCS CENTUM CS3000R3
you need to use Siemens CS-3000 module to convert your signal to modbus TCP/IP signal and interface...
By Patrick Lansdorf on 10 April, 2014 - 2:17 am -
Hi, I am guessing that the PLC is a Profibus master... You can use a gateway, such as: ...
from the Forum department...Flow Rate Calculations S7-1200
Flow Rate Calculations S7-1200
from the Forum department...2oo3D voting
Explain if 1oo2D voting is just similar to 2oo3 voting for ESD system.
Let's start with your requirement of tripping of valve on rise of line pressure beyond high limit....
from the HC900-C70R department...Split Range Control on two valves - HC900-C70R
Split Range Control on two valves - HC900-C70R
The pressure transmitter is the input to an analog input function block. Its analog value is the...
from the Forum department...WinConX driver (MBX driver 4.2)
I need the WinConX driver (MBX driver 4.2) to install an old PCI-85 card
By Benoit on 8 April, 2014 - 2:26 pm -
Contact your local Schneider Modicon representative. They might be able to give you a complimentary...
from the Over the Cliff department...Siemens S7 programming
Siemens S7 programming
By JC on 6 April, 2014 - 8:10 pm -
I take issue with this assessment. Take your example of C vs Visual Basic. There's a dramatic...
from the Instrument department...ABB Thermocouple Transmitter reading fluctuates
Transmitters reading Fluctuating
Okay, You answered some of the questions. Have you checked the thermocouples in the stack to...
first off all i am sorry for writing down transmitter model is ABB TH02. the answer of your...
from the Forum department...Tri-Sen analog output low
Tri-sen TS 310 controller that doesn't want to output a full 20 ma signal
By Curt Wuollet on 31 March, 2014 - 11:40 pm -
Possibly a compliance voltage issue? If the load is too light for some reason there isn't enough...
Page 40 of the TS310 User Guide states that the voltage driving the output is 7 volts and that an...
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